Are there any attested Classical Latin words whose meanings are unknown to us?

Given the intensive study of the Classical Latin corpus and the many methods of getting at the meanings of words (including etymological relations either to modern Romance or to other Indogermanic languages) I wonder if some such words are left. What are examples of such words?

@JoonasIlmavirta No I haven't seen it (and it wasn't suggested while typing my question in, but maybe I was just too fast)
– jknappenDec 22 '18 at 15:03

I'd say to keep this question, as it's not exactly a duplicate of the previous one and it leads in a different direction. This one leads me to think that words for colors might provide some good examples, e.g. caeruleus: sky blue, sea blue (dark blue), dark green, dark regardless of color? Similarly words for elements of rituals, offices, and foods—words whose meanings likely shifted over centuries and have little documentation. Someone more knowledge might know a definitive collection of these.
– Ben KovitzDec 23 '18 at 23:49